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Console Errors
JavaScript errors, warnings, and unhandled rejections captured from the console.
TypeError: Property of Undefined
Console
Accesses a property on null — the most common JS runtime error.
Console error: TypeError with stack trace
ReferenceError: Undefined Variable
Console
References a variable that was never declared — common typo/import error.
Console error: ReferenceError with variable name
RangeError: Stack Overflow
Console
Infinite recursion causing a stack overflow. Tests stack trace truncation (2000 char limit).
Console error: RangeError, stack truncated at 2000 chars
SyntaxError via eval()
Console
Evaluates malformed JavaScript — a parse-time error.
Console error: SyntaxError with parse details
Unhandled Promise Rejection
Console
A promise rejected without a .catch() — captured via the unhandledrejection event.
Console error: "Unhandled rejection:" prefix with rejection reason
Async Error (setTimeout)
Console
An error thrown inside setTimeout escapes try/catch and is caught by the global error handler.
Console error: caught by window error event listener
console.warn()
Console
A deprecation warning logged via console.warn — captured with level "warn".
Console event: level "warn" with message
console.log with Large Object
Console
Logs a large serialized object — tests the 1000 character message truncation.
Console event: message truncated at 1000 chars
console.error with Multiple Args
Console
Passes multiple arguments to console.error — all get serialized and joined.
Console error: all arguments joined in message